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We consider a finite mixture model with varying mixing probabilities. Linear regression models are assumed for observed variables with coefficients depending on the mixture component the observed subject belongs to. A modification of the…

Probability · Mathematics 2016-01-07 Daryna Liubashenko , Rostyslav Maiboroda

Expanding a lower-dimensional problem to a higher-dimensional space and then projecting back is often beneficial. This article rigorously investigates this perspective in the context of finite mixture models, namely how to improve inference…

Methodology · Statistics 2014-11-10 Andrea Mercatanti , Fan Li , Fabrizia Mealli

Causal representation learning aims at identifying high-level causal variables from perceptual data. Most methods assume that all latent causal variables are captured in the high-dimensional observations. We instead consider a partially…

Although continuous density estimation has received abundant attention in the Bayesian nonparametrics literature, there is limited theory on multivariate mixed scale density estimation. In this note, we consider a general framework to…

Statistics Theory · Mathematics 2014-05-26 Antonio Canale , David B. Dunson

We reconsider a nonparametric density model based on Gaussian processes. By augmenting the model with latent P\'olya--Gamma random variables and a latent marked Poisson process we obtain a new likelihood which is conjugate to the model's…

Machine Learning · Statistics 2018-05-30 Christian Donner , Manfred Opper

We propose a class of structured diffusion models, in which the prior distribution is chosen as a mixture of Gaussians, rather than a standard Gaussian distribution. The specific mixed Gaussian distribution, as prior, can be chosen to…

Machine Learning · Computer Science 2024-10-28 Nanshan Jia , Tingyu Zhu , Haoyu Liu , Zeyu Zheng

We consider a binary unsupervised classification problem where each observation is associated with an unobserved label that we want to retrieve. More precisely, we assume that there are two groups of observation: normal and abnormal. The…

Machine Learning · Statistics 2011-05-05 Stevenn Volant , Marie-Laure Martin Magniette , Stéphane Robin

The use of Gaussian process models is typically limited to datasets with a few tens of thousands of observations due to their complexity and memory footprint. The two most commonly used methods to overcome this limitation are 1) the…

Machine Learning · Statistics 2020-01-16 Vincent Adam , Stefanos Eleftheriadis , Nicolas Durrande , Artem Artemev , James Hensman

In many applications, multivariate samples may harbor previously unrecognized heterogeneity at the level of conditional independence or network structure. For example, in cancer biology, disease subtypes may differ with respect to…

Machine Learning · Statistics 2013-01-11 Steven M. Hill , Sach Mukherjee

Item nonresponse is frequently encountered in practice. Ignoring missing data can lose efficiency and lead to misleading inference. Fractional imputation is a frequentist approach of imputation for handling missing data. However, the…

Methodology · Statistics 2018-09-18 Hejian Sang , Jae Kwang Kim

Recently there has been an increasing interest in methods that deal with multiple outputs. This has been motivated partly by frameworks like multitask learning, multisensor networks or structured output data. From a Gaussian processes…

Machine Learning · Statistics 2009-11-30 Mauricio A. Álvarez , Neil D. Lawrence

The mixture of Gaussian distributions, a soft version of k-means , is considered a state-of-the-art clustering algorithm. It is widely used in computer vision for selecting classes, e.g., color, texture, and shapes. In this algorithm, each…

Machine Learning · Statistics 2016-12-30 Mahajabin Rahman , Davi Geiger

Gaussian Processes (GP) have become popular machine-learning methods for kernel-based learning on datasets with complicated covariance structures. In this paper, we present a novel extension to the GP framework using a contaminated normal…

Machine Learning · Computer Science 2024-07-03 Daniel Iong , Matthew McAnear , Yuezhou Qu , Shasha Zou , Gabor Toth , Yang Chen

This paper deals with Bayesian inference of a mixture of Gaussian distributions. A novel formulation of the mixture model is introduced, which includes the prior constraint that each Gaussian component is always assigned a minimal number of…

Methodology · Statistics 2014-05-21 Colin J. Stoneking

In the problem of learning mixtures of linear regressions, the goal is to learn a collection of signal vectors from a sequence of (possibly noisy) linear measurements, where each measurement is evaluated on an unknown signal drawn uniformly…

Machine Learning · Computer Science 2019-11-01 Akshay Krishnamurthy , Arya Mazumdar , Andrew McGregor , Soumyabrata Pal

Multi-task learning models using Gaussian processes (GP) have been developed and successfully applied in various applications. The main difficulty with this approach is the computational cost of inference using the union of examples from…

Machine Learning · Computer Science 2012-11-29 Yuyang Wang , Roni Khardon

Measuring the impact of an environmental point source exposure on the risk of disease, like cancer or childhood asthma, is well-developed. Modeling how an environmental health hazard that is extensive in space, like a wastewater canal,…

Methodology · Statistics 2024-07-29 Rob Trangucci , Jesse Contreras , Jon Zelner , Joseph N. S. Eisenberg , Yang Chen

Because of its mathematical tractability, the Gaussian mixture model holds a special place in the literature for clustering and classification. For all its benefits, however, the Gaussian mixture model poses problems when the data is skewed…

Applications · Statistics 2020-11-19 Michael P. B. Gallaugher , Paul D. McNicholas , Volodymyr Melnykov , Xuwen Zhu

In this paper, a scale mixture of Normal distributions model is developed for classification and clustering of data having outliers and missing values. The classification method, based on a mixture model, focuses on the introduction of…

Machine Learning · Statistics 2017-11-23 G. Revillon , A. Djafari , C. Enderli

Gaussian mixture models are widely used to model data generated from multiple latent sources. Despite its popularity, most theoretical research assumes that the labels are either independent and identically distributed, or follows a Markov…

Statistics Theory · Mathematics 2025-10-09 Seunghyun Lee , Rajarshi Mukherjee , Sumit Mukherjee